/*
 * Copyright 2011 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "skia/ext/skia_matrix_44.h"
#include <type_traits>
#include <utility>

namespace skia {

// Copying Matrix44 byte-wise is performance-critical to Blink. This class is
// contained in several Transform classes, which are copied multiple times
// during the rendering life cycle. See crbug.com/938563 for reference.
#if defined(SK_BUILD_FOR_WIN) || defined(SK_BUILD_FOR_MAC)
// std::is_trivially_copyable is not supported for some older clang versions,
// which (at least as of this patch) are in use for Chromecast.
static_assert(std::is_trivially_copyable<Matrix44>::value,
              "Matrix44 must be trivially copyable");
#endif

static inline bool eq4(const SkScalar* SK_RESTRICT a,
                       const SkScalar* SK_RESTRICT b) {
  return (a[0] == b[0]) & (a[1] == b[1]) & (a[2] == b[2]) & (a[3] == b[3]);
}

bool Matrix44::operator==(const Matrix44& other) const {
  if (this == &other) {
    return true;
  }

  if (this->isIdentity() && other.isIdentity()) {
    return true;
  }

  const SkScalar* SK_RESTRICT a = &fMat[0][0];
  const SkScalar* SK_RESTRICT b = &other.fMat[0][0];

#if 0
    for (int i = 0; i < 16; ++i) {
        if (a[i] != b[i]) {
            return false;
        }
    }
    return true;
#else
  // to reduce branch instructions, we compare 4 at a time.
  // see bench/Matrix44Bench.cpp for test.
  if (!eq4(&a[0], &b[0])) {
    return false;
  }
  if (!eq4(&a[4], &b[4])) {
    return false;
  }
  if (!eq4(&a[8], &b[8])) {
    return false;
  }
  return eq4(&a[12], &b[12]);
#endif
}

///////////////////////////////////////////////////////////////////////////////
void Matrix44::recomputeTypeMask() {
  if (0 != perspX() || 0 != perspY() || 0 != perspZ() || 1 != fMat[3][3]) {
    fTypeMask =
        kTranslate_Mask | kScale_Mask | kAffine_Mask | kPerspective_Mask;
    return;
  }

  TypeMask mask = kIdentity_Mask;
  if (0 != transX() || 0 != transY() || 0 != transZ()) {
    mask |= kTranslate_Mask;
  }

  if (1 != scaleX() || 1 != scaleY() || 1 != scaleZ()) {
    mask |= kScale_Mask;
  }

  if (0 != fMat[1][0] || 0 != fMat[0][1] || 0 != fMat[0][2] ||
      0 != fMat[2][0] || 0 != fMat[1][2] || 0 != fMat[2][1]) {
    mask |= kAffine_Mask;
  }
  fTypeMask = mask;
}

///////////////////////////////////////////////////////////////////////////////

void Matrix44::asColMajorf(float dst[]) const {
  const SkScalar* src = &fMat[0][0];
  for (int i = 0; i < 16; ++i) {
    dst[i] = src[i];
  }
}

void Matrix44::as3x4RowMajorf(float dst[]) const {
  dst[0] = fMat[0][0];
  dst[1] = fMat[1][0];
  dst[2] = fMat[2][0];
  dst[3] = fMat[3][0];
  dst[4] = fMat[0][1];
  dst[5] = fMat[1][1];
  dst[6] = fMat[2][1];
  dst[7] = fMat[3][1];
  dst[8] = fMat[0][2];
  dst[9] = fMat[1][2];
  dst[10] = fMat[2][2];
  dst[11] = fMat[3][2];
}

void Matrix44::asColMajord(double dst[]) const {
  const SkScalar* src = &fMat[0][0];
  for (int i = 0; i < 16; ++i) {
    dst[i] = src[i];
  }
}

void Matrix44::asRowMajorf(float dst[]) const {
  const SkScalar* src = &fMat[0][0];
  for (int i = 0; i < 4; ++i) {
    dst[0] = float(src[0]);
    dst[4] = float(src[1]);
    dst[8] = float(src[2]);
    dst[12] = float(src[3]);
    src += 4;
    dst += 1;
  }
}

void Matrix44::asRowMajord(double dst[]) const {
  const SkScalar* src = &fMat[0][0];
  for (int i = 0; i < 4; ++i) {
    dst[0] = src[0];
    dst[4] = src[1];
    dst[8] = src[2];
    dst[12] = src[3];
    src += 4;
    dst += 1;
  }
}

void Matrix44::setColMajorf(const float src[]) {
  SkScalar* dst = &fMat[0][0];
  for (int i = 0; i < 16; ++i) {
    dst[i] = src[i];
  }

  this->recomputeTypeMask();
}

void Matrix44::setColMajord(const double src[]) {
  SkScalar* dst = &fMat[0][0];
  for (int i = 0; i < 16; ++i) {
    dst[i] = SkScalar(src[i]);
  }

  this->recomputeTypeMask();
}

void Matrix44::setRowMajorf(const float src[]) {
  SkScalar* dst = &fMat[0][0];
  for (int i = 0; i < 4; ++i) {
    dst[0] = src[0];
    dst[4] = src[1];
    dst[8] = src[2];
    dst[12] = src[3];
    src += 4;
    dst += 1;
  }
  this->recomputeTypeMask();
}

void Matrix44::setRowMajord(const double src[]) {
  SkScalar* dst = &fMat[0][0];
  for (int i = 0; i < 4; ++i) {
    dst[0] = SkScalar(src[0]);
    dst[4] = SkScalar(src[1]);
    dst[8] = SkScalar(src[2]);
    dst[12] = SkScalar(src[3]);
    src += 4;
    dst += 1;
  }
  this->recomputeTypeMask();
}

///////////////////////////////////////////////////////////////////////////////

const Matrix44& Matrix44::I() {
  static constexpr Matrix44 gIdentity44(kIdentity_Constructor);
  return gIdentity44;
}

void Matrix44::setIdentity() {
  fMat[0][0] = 1;
  fMat[0][1] = 0;
  fMat[0][2] = 0;
  fMat[0][3] = 0;
  fMat[1][0] = 0;
  fMat[1][1] = 1;
  fMat[1][2] = 0;
  fMat[1][3] = 0;
  fMat[2][0] = 0;
  fMat[2][1] = 0;
  fMat[2][2] = 1;
  fMat[2][3] = 0;
  fMat[3][0] = 0;
  fMat[3][1] = 0;
  fMat[3][2] = 0;
  fMat[3][3] = 1;
  this->setTypeMask(kIdentity_Mask);
}

void Matrix44::set3x3(SkScalar m_00,
                      SkScalar m_10,
                      SkScalar m_20,
                      SkScalar m_01,
                      SkScalar m_11,
                      SkScalar m_21,
                      SkScalar m_02,
                      SkScalar m_12,
                      SkScalar m_22) {
  fMat[0][0] = m_00;
  fMat[0][1] = m_10;
  fMat[0][2] = m_20;
  fMat[0][3] = 0;
  fMat[1][0] = m_01;
  fMat[1][1] = m_11;
  fMat[1][2] = m_21;
  fMat[1][3] = 0;
  fMat[2][0] = m_02;
  fMat[2][1] = m_12;
  fMat[2][2] = m_22;
  fMat[2][3] = 0;
  fMat[3][0] = 0;
  fMat[3][1] = 0;
  fMat[3][2] = 0;
  fMat[3][3] = 1;
  this->recomputeTypeMask();
}

void Matrix44::set3x3RowMajorf(const float src[]) {
  fMat[0][0] = src[0];
  fMat[0][1] = src[3];
  fMat[0][2] = src[6];
  fMat[0][3] = 0;
  fMat[1][0] = src[1];
  fMat[1][1] = src[4];
  fMat[1][2] = src[7];
  fMat[1][3] = 0;
  fMat[2][0] = src[2];
  fMat[2][1] = src[5];
  fMat[2][2] = src[8];
  fMat[2][3] = 0;
  fMat[3][0] = 0;
  fMat[3][1] = 0;
  fMat[3][2] = 0;
  fMat[3][3] = 1;
  this->recomputeTypeMask();
}

void Matrix44::set3x4RowMajorf(const float src[]) {
  fMat[0][0] = src[0];
  fMat[1][0] = src[1];
  fMat[2][0] = src[2];
  fMat[3][0] = src[3];
  fMat[0][1] = src[4];
  fMat[1][1] = src[5];
  fMat[2][1] = src[6];
  fMat[3][1] = src[7];
  fMat[0][2] = src[8];
  fMat[1][2] = src[9];
  fMat[2][2] = src[10];
  fMat[3][2] = src[11];
  fMat[0][3] = 0;
  fMat[1][3] = 0;
  fMat[2][3] = 0;
  fMat[3][3] = 1;
  this->recomputeTypeMask();
}

void Matrix44::set4x4(SkScalar m_00,
                      SkScalar m_10,
                      SkScalar m_20,
                      SkScalar m_30,
                      SkScalar m_01,
                      SkScalar m_11,
                      SkScalar m_21,
                      SkScalar m_31,
                      SkScalar m_02,
                      SkScalar m_12,
                      SkScalar m_22,
                      SkScalar m_32,
                      SkScalar m_03,
                      SkScalar m_13,
                      SkScalar m_23,
                      SkScalar m_33) {
  fMat[0][0] = m_00;
  fMat[0][1] = m_10;
  fMat[0][2] = m_20;
  fMat[0][3] = m_30;
  fMat[1][0] = m_01;
  fMat[1][1] = m_11;
  fMat[1][2] = m_21;
  fMat[1][3] = m_31;
  fMat[2][0] = m_02;
  fMat[2][1] = m_12;
  fMat[2][2] = m_22;
  fMat[2][3] = m_32;
  fMat[3][0] = m_03;
  fMat[3][1] = m_13;
  fMat[3][2] = m_23;
  fMat[3][3] = m_33;
  this->recomputeTypeMask();
}

///////////////////////////////////////////////////////////////////////////////

Matrix44& Matrix44::setTranslate(SkScalar dx, SkScalar dy, SkScalar dz) {
  this->setIdentity();

  if (!dx && !dy && !dz) {
    return *this;
  }

  fMat[3][0] = dx;
  fMat[3][1] = dy;
  fMat[3][2] = dz;
  this->setTypeMask(kTranslate_Mask);
  return *this;
}

Matrix44& Matrix44::preTranslate(SkScalar dx, SkScalar dy, SkScalar dz) {
  if (!dx && !dy && !dz) {
    return *this;
  }

  for (int i = 0; i < 4; ++i) {
    fMat[3][i] =
        fMat[0][i] * dx + fMat[1][i] * dy + fMat[2][i] * dz + fMat[3][i];
  }
  this->recomputeTypeMask();
  return *this;
}

Matrix44& Matrix44::postTranslate(SkScalar dx, SkScalar dy, SkScalar dz) {
  if (!dx && !dy && !dz) {
    return *this;
  }

  if (this->getType() & kPerspective_Mask) {
    for (int i = 0; i < 4; ++i) {
      fMat[i][0] += fMat[i][3] * dx;
      fMat[i][1] += fMat[i][3] * dy;
      fMat[i][2] += fMat[i][3] * dz;
    }
  } else {
    fMat[3][0] += dx;
    fMat[3][1] += dy;
    fMat[3][2] += dz;
    this->recomputeTypeMask();
  }
  return *this;
}

///////////////////////////////////////////////////////////////////////////////

Matrix44& Matrix44::setScale(SkScalar sx, SkScalar sy, SkScalar sz) {
  this->setIdentity();

  if (1 == sx && 1 == sy && 1 == sz) {
    return *this;
  }

  fMat[0][0] = sx;
  fMat[1][1] = sy;
  fMat[2][2] = sz;
  this->setTypeMask(kScale_Mask);
  return *this;
}

Matrix44& Matrix44::preScale(SkScalar sx, SkScalar sy, SkScalar sz) {
  if (1 == sx && 1 == sy && 1 == sz) {
    return *this;
  }

  // The implementation matrix * pureScale can be shortcut
  // by knowing that pureScale components effectively scale
  // the columns of the original matrix.
  for (int i = 0; i < 4; i++) {
    fMat[0][i] *= sx;
    fMat[1][i] *= sy;
    fMat[2][i] *= sz;
  }
  this->recomputeTypeMask();
  return *this;
}

Matrix44& Matrix44::postScale(SkScalar sx, SkScalar sy, SkScalar sz) {
  if (1 == sx && 1 == sy && 1 == sz) {
    return *this;
  }

  for (int i = 0; i < 4; i++) {
    fMat[i][0] *= sx;
    fMat[i][1] *= sy;
    fMat[i][2] *= sz;
  }
  this->recomputeTypeMask();
  return *this;
}

///////////////////////////////////////////////////////////////////////////////

void Matrix44::setRotateAbout(SkScalar x,
                              SkScalar y,
                              SkScalar z,
                              SkScalar radians) {
  double len2 = static_cast<double>(x) * x + static_cast<double>(y) * y +
                static_cast<double>(z) * z;
  if (1 != len2) {
    if (0 == len2) {
      this->setIdentity();
      return;
    }
    double scale = 1 / sqrt(len2);
    x = SkScalar(x * scale);
    y = SkScalar(y * scale);
    z = SkScalar(z * scale);
  }
  this->setRotateAboutUnit(x, y, z, radians);
}

void Matrix44::setRotateAboutUnit(SkScalar x,
                                  SkScalar y,
                                  SkScalar z,
                                  SkScalar radians) {
  double c = cos(radians);
  double s = sin(radians);
  double C = 1 - c;
  double xs = x * s;
  double ys = y * s;
  double zs = z * s;
  double xC = x * C;
  double yC = y * C;
  double zC = z * C;
  double xyC = x * yC;
  double yzC = y * zC;
  double zxC = z * xC;

  // if you're looking at wikipedia, remember that we're column major.
  this->set3x3(SkScalar(x * xC + c),  // scale x
               SkScalar(xyC + zs),    // skew x
               SkScalar(zxC - ys),    // trans x

               SkScalar(xyC - zs),    // skew y
               SkScalar(y * yC + c),  // scale y
               SkScalar(yzC + xs),    // trans y

               SkScalar(zxC + ys),     // persp x
               SkScalar(yzC - xs),     // persp y
               SkScalar(z * zC + c));  // persp 2
}

///////////////////////////////////////////////////////////////////////////////

static bool bits_isonly(int value, int mask) {
  return 0 == (value & ~mask);
}

void Matrix44::setConcat(const Matrix44& a, const Matrix44& b) {
  const Matrix44::TypeMask a_mask = a.getType();
  const Matrix44::TypeMask b_mask = b.getType();

  if (kIdentity_Mask == a_mask) {
    *this = b;
    return;
  }
  if (kIdentity_Mask == b_mask) {
    *this = a;
    return;
  }

  bool useStorage = (this == &a || this == &b);
  SkScalar storage[16];
  SkScalar* result = useStorage ? storage : &fMat[0][0];

  // Both matrices are at most scale+translate
  if (bits_isonly(a_mask | b_mask, kScale_Mask | kTranslate_Mask)) {
    result[0] = a.fMat[0][0] * b.fMat[0][0];
    result[1] = result[2] = result[3] = result[4] = 0;
    result[5] = a.fMat[1][1] * b.fMat[1][1];
    result[6] = result[7] = result[8] = result[9] = 0;
    result[10] = a.fMat[2][2] * b.fMat[2][2];
    result[11] = 0;
    result[12] = a.fMat[0][0] * b.fMat[3][0] + a.fMat[3][0];
    result[13] = a.fMat[1][1] * b.fMat[3][1] + a.fMat[3][1];
    result[14] = a.fMat[2][2] * b.fMat[3][2] + a.fMat[3][2];
    result[15] = 1;
  } else {
    for (int j = 0; j < 4; j++) {
      for (int i = 0; i < 4; i++) {
        double value = 0;
        for (int k = 0; k < 4; k++) {
          value += double(a.fMat[k][i]) * b.fMat[j][k];
        }
        *result++ = SkScalar(value);
      }
    }
  }

  if (useStorage) {
    memcpy(fMat, storage, sizeof(storage));
  }
  this->recomputeTypeMask();
}

///////////////////////////////////////////////////////////////////////////////

/** We always perform the calculation in doubles, to avoid prematurely losing
    precision along the way. This relies on the compiler automatically
    promoting our SkScalar values to double (if needed).
 */
double Matrix44::determinant() const {
  if (this->isIdentity()) {
    return 1;
  }
  if (this->isScaleTranslate()) {
    return fMat[0][0] * fMat[1][1] * fMat[2][2] * fMat[3][3];
  }

  double a00 = fMat[0][0];
  double a01 = fMat[0][1];
  double a02 = fMat[0][2];
  double a03 = fMat[0][3];
  double a10 = fMat[1][0];
  double a11 = fMat[1][1];
  double a12 = fMat[1][2];
  double a13 = fMat[1][3];
  double a20 = fMat[2][0];
  double a21 = fMat[2][1];
  double a22 = fMat[2][2];
  double a23 = fMat[2][3];
  double a30 = fMat[3][0];
  double a31 = fMat[3][1];
  double a32 = fMat[3][2];
  double a33 = fMat[3][3];

  double b00 = a00 * a11 - a01 * a10;
  double b01 = a00 * a12 - a02 * a10;
  double b02 = a00 * a13 - a03 * a10;
  double b03 = a01 * a12 - a02 * a11;
  double b04 = a01 * a13 - a03 * a11;
  double b05 = a02 * a13 - a03 * a12;
  double b06 = a20 * a31 - a21 * a30;
  double b07 = a20 * a32 - a22 * a30;
  double b08 = a20 * a33 - a23 * a30;
  double b09 = a21 * a32 - a22 * a31;
  double b10 = a21 * a33 - a23 * a31;
  double b11 = a22 * a33 - a23 * a32;

  // Calculate the determinant
  return b00 * b11 - b01 * b10 + b02 * b09 + b03 * b08 - b04 * b07 + b05 * b06;
}

///////////////////////////////////////////////////////////////////////////////

static bool is_matrix_finite(const Matrix44& matrix) {
  SkScalar accumulator = 0;
  for (int row = 0; row < 4; ++row) {
    for (int col = 0; col < 4; ++col) {
      accumulator *= matrix.get(row, col);
    }
  }
  return accumulator == 0;
}

bool Matrix44::invert(Matrix44* storage) const {
  if (this->isIdentity()) {
    if (storage) {
      storage->setIdentity();
    }
    return true;
  }

  if (this->isTranslate()) {
    if (storage) {
      storage->setTranslate(-fMat[3][0], -fMat[3][1], -fMat[3][2]);
    }
    return true;
  }

  Matrix44 tmp;
  // Use storage if it's available and distinct from this matrix.
  Matrix44* inverse = (storage && storage != this) ? storage : &tmp;
  if (this->isScaleTranslate()) {
    if (0 == fMat[0][0] * fMat[1][1] * fMat[2][2]) {
      return false;
    }

    double invXScale = 1 / fMat[0][0];
    double invYScale = 1 / fMat[1][1];
    double invZScale = 1 / fMat[2][2];

    inverse->fMat[0][0] = SkDoubleToScalar(invXScale);
    inverse->fMat[0][1] = 0;
    inverse->fMat[0][2] = 0;
    inverse->fMat[0][3] = 0;

    inverse->fMat[1][0] = 0;
    inverse->fMat[1][1] = SkDoubleToScalar(invYScale);
    inverse->fMat[1][2] = 0;
    inverse->fMat[1][3] = 0;

    inverse->fMat[2][0] = 0;
    inverse->fMat[2][1] = 0;
    inverse->fMat[2][2] = SkDoubleToScalar(invZScale);
    inverse->fMat[2][3] = 0;

    inverse->fMat[3][0] = SkDoubleToScalar(-fMat[3][0] * invXScale);
    inverse->fMat[3][1] = SkDoubleToScalar(-fMat[3][1] * invYScale);
    inverse->fMat[3][2] = SkDoubleToScalar(-fMat[3][2] * invZScale);
    inverse->fMat[3][3] = 1;

    inverse->setTypeMask(this->getType());

    if (!is_matrix_finite(*inverse)) {
      return false;
    }
    if (storage && inverse != storage) {
      *storage = *inverse;
    }
    return true;
  }

  double a00 = fMat[0][0];
  double a01 = fMat[0][1];
  double a02 = fMat[0][2];
  double a03 = fMat[0][3];
  double a10 = fMat[1][0];
  double a11 = fMat[1][1];
  double a12 = fMat[1][2];
  double a13 = fMat[1][3];
  double a20 = fMat[2][0];
  double a21 = fMat[2][1];
  double a22 = fMat[2][2];
  double a23 = fMat[2][3];
  double a30 = fMat[3][0];
  double a31 = fMat[3][1];
  double a32 = fMat[3][2];
  double a33 = fMat[3][3];

  if (!(this->getType() & kPerspective_Mask)) {
    // If we know the matrix has no perspective, then the perspective
    // component is (0, 0, 0, 1). We can use this information to save a lot
    // of arithmetic that would otherwise be spent to compute the inverse
    // of a general matrix.

    SkASSERT(a03 == 0);
    SkASSERT(a13 == 0);
    SkASSERT(a23 == 0);
    SkASSERT(a33 == 1);

    double b00 = a00 * a11 - a01 * a10;
    double b01 = a00 * a12 - a02 * a10;
    double b03 = a01 * a12 - a02 * a11;
    double b06 = a20 * a31 - a21 * a30;
    double b07 = a20 * a32 - a22 * a30;
    double b08 = a20;
    double b09 = a21 * a32 - a22 * a31;
    double b10 = a21;
    double b11 = a22;

    // Calculate the determinant
    double det = b00 * b11 - b01 * b10 + b03 * b08;

    double invdet = sk_ieee_double_divide(1.0, det);
    // If det is zero, we want to return false. However, we also want to return
    // false if 1/det overflows to infinity (i.e. det is denormalized). Both of
    // these are handled by checking that 1/det is finite.
    if (!sk_float_isfinite(sk_double_to_float(invdet))) {
      return false;
    }

    b00 *= invdet;
    b01 *= invdet;
    b03 *= invdet;
    b06 *= invdet;
    b07 *= invdet;
    b08 *= invdet;
    b09 *= invdet;
    b10 *= invdet;
    b11 *= invdet;

    inverse->fMat[0][0] = SkDoubleToScalar(a11 * b11 - a12 * b10);
    inverse->fMat[0][1] = SkDoubleToScalar(a02 * b10 - a01 * b11);
    inverse->fMat[0][2] = SkDoubleToScalar(b03);
    inverse->fMat[0][3] = 0;
    inverse->fMat[1][0] = SkDoubleToScalar(a12 * b08 - a10 * b11);
    inverse->fMat[1][1] = SkDoubleToScalar(a00 * b11 - a02 * b08);
    inverse->fMat[1][2] = SkDoubleToScalar(-b01);
    inverse->fMat[1][3] = 0;
    inverse->fMat[2][0] = SkDoubleToScalar(a10 * b10 - a11 * b08);
    inverse->fMat[2][1] = SkDoubleToScalar(a01 * b08 - a00 * b10);
    inverse->fMat[2][2] = SkDoubleToScalar(b00);
    inverse->fMat[2][3] = 0;
    inverse->fMat[3][0] = SkDoubleToScalar(a11 * b07 - a10 * b09 - a12 * b06);
    inverse->fMat[3][1] = SkDoubleToScalar(a00 * b09 - a01 * b07 + a02 * b06);
    inverse->fMat[3][2] = SkDoubleToScalar(a31 * b01 - a30 * b03 - a32 * b00);
    inverse->fMat[3][3] = 1;

    inverse->setTypeMask(this->getType());
    if (!is_matrix_finite(*inverse)) {
      return false;
    }
    if (storage && inverse != storage) {
      *storage = *inverse;
    }
    return true;
  }

  double b00 = a00 * a11 - a01 * a10;
  double b01 = a00 * a12 - a02 * a10;
  double b02 = a00 * a13 - a03 * a10;
  double b03 = a01 * a12 - a02 * a11;
  double b04 = a01 * a13 - a03 * a11;
  double b05 = a02 * a13 - a03 * a12;
  double b06 = a20 * a31 - a21 * a30;
  double b07 = a20 * a32 - a22 * a30;
  double b08 = a20 * a33 - a23 * a30;
  double b09 = a21 * a32 - a22 * a31;
  double b10 = a21 * a33 - a23 * a31;
  double b11 = a22 * a33 - a23 * a32;

  // Calculate the determinant
  double det =
      b00 * b11 - b01 * b10 + b02 * b09 + b03 * b08 - b04 * b07 + b05 * b06;

  double invdet = sk_ieee_double_divide(1.0, det);
  // If det is zero, we want to return false. However, we also want to return
  // false if 1/det overflows to infinity (i.e. det is denormalized). Both of
  // these are handled by checking that 1/det is finite.
  if (!sk_float_isfinite(sk_double_to_float(invdet))) {
    return false;
  }

  b00 *= invdet;
  b01 *= invdet;
  b02 *= invdet;
  b03 *= invdet;
  b04 *= invdet;
  b05 *= invdet;
  b06 *= invdet;
  b07 *= invdet;
  b08 *= invdet;
  b09 *= invdet;
  b10 *= invdet;
  b11 *= invdet;

  inverse->fMat[0][0] = SkDoubleToScalar(a11 * b11 - a12 * b10 + a13 * b09);
  inverse->fMat[0][1] = SkDoubleToScalar(a02 * b10 - a01 * b11 - a03 * b09);
  inverse->fMat[0][2] = SkDoubleToScalar(a31 * b05 - a32 * b04 + a33 * b03);
  inverse->fMat[0][3] = SkDoubleToScalar(a22 * b04 - a21 * b05 - a23 * b03);
  inverse->fMat[1][0] = SkDoubleToScalar(a12 * b08 - a10 * b11 - a13 * b07);
  inverse->fMat[1][1] = SkDoubleToScalar(a00 * b11 - a02 * b08 + a03 * b07);
  inverse->fMat[1][2] = SkDoubleToScalar(a32 * b02 - a30 * b05 - a33 * b01);
  inverse->fMat[1][3] = SkDoubleToScalar(a20 * b05 - a22 * b02 + a23 * b01);
  inverse->fMat[2][0] = SkDoubleToScalar(a10 * b10 - a11 * b08 + a13 * b06);
  inverse->fMat[2][1] = SkDoubleToScalar(a01 * b08 - a00 * b10 - a03 * b06);
  inverse->fMat[2][2] = SkDoubleToScalar(a30 * b04 - a31 * b02 + a33 * b00);
  inverse->fMat[2][3] = SkDoubleToScalar(a21 * b02 - a20 * b04 - a23 * b00);
  inverse->fMat[3][0] = SkDoubleToScalar(a11 * b07 - a10 * b09 - a12 * b06);
  inverse->fMat[3][1] = SkDoubleToScalar(a00 * b09 - a01 * b07 + a02 * b06);
  inverse->fMat[3][2] = SkDoubleToScalar(a31 * b01 - a30 * b03 - a32 * b00);
  inverse->fMat[3][3] = SkDoubleToScalar(a20 * b03 - a21 * b01 + a22 * b00);
  inverse->setTypeMask(this->getType());
  if (!is_matrix_finite(*inverse)) {
    return false;
  }
  if (storage && inverse != storage) {
    *storage = *inverse;
  }
  return true;
}

///////////////////////////////////////////////////////////////////////////////

void Matrix44::transpose() {
  if (!this->isIdentity()) {
    using std::swap;
    swap(fMat[0][1], fMat[1][0]);
    swap(fMat[0][2], fMat[2][0]);
    swap(fMat[0][3], fMat[3][0]);
    swap(fMat[1][2], fMat[2][1]);
    swap(fMat[1][3], fMat[3][1]);
    swap(fMat[2][3], fMat[3][2]);
    this->recomputeTypeMask();
  }
}

///////////////////////////////////////////////////////////////////////////////

void Matrix44::mapScalars(const SkScalar src[4], SkScalar dst[4]) const {
  SkScalar storage[4];
  SkScalar* result = (src == dst) ? storage : dst;

  for (int i = 0; i < 4; i++) {
    SkScalar value = 0;
    for (int j = 0; j < 4; j++) {
      value += fMat[j][i] * src[j];
    }
    result[i] = value;
  }

  if (storage == result) {
    memcpy(dst, storage, sizeof(storage));
  }
}

typedef void (*Map2Procf)(const SkScalar mat[][4],
                          const float src2[],
                          int count,
                          float dst4[]);
typedef void (*Map2Procd)(const SkScalar mat[][4],
                          const double src2[],
                          int count,
                          double dst4[]);

static void map2_if(const SkScalar mat[][4],
                    const float* SK_RESTRICT src2,
                    int count,
                    float* SK_RESTRICT dst4) {
  for (int i = 0; i < count; ++i) {
    dst4[0] = src2[0];
    dst4[1] = src2[1];
    dst4[2] = 0;
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_id(const SkScalar mat[][4],
                    const double* SK_RESTRICT src2,
                    int count,
                    double* SK_RESTRICT dst4) {
  for (int i = 0; i < count; ++i) {
    dst4[0] = src2[0];
    dst4[1] = src2[1];
    dst4[2] = 0;
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_tf(const SkScalar mat[][4],
                    const float* SK_RESTRICT src2,
                    int count,
                    float* SK_RESTRICT dst4) {
  const float mat30 = float(mat[3][0]);
  const float mat31 = float(mat[3][1]);
  const float mat32 = float(mat[3][2]);
  for (int n = 0; n < count; ++n) {
    dst4[0] = src2[0] + mat30;
    dst4[1] = src2[1] + mat31;
    dst4[2] = mat32;
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_td(const SkScalar mat[][4],
                    const double* SK_RESTRICT src2,
                    int count,
                    double* SK_RESTRICT dst4) {
  for (int n = 0; n < count; ++n) {
    dst4[0] = src2[0] + mat[3][0];
    dst4[1] = src2[1] + mat[3][1];
    dst4[2] = mat[3][2];
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_sf(const SkScalar mat[][4],
                    const float* SK_RESTRICT src2,
                    int count,
                    float* SK_RESTRICT dst4) {
  const float mat32 = float(mat[3][2]);
  for (int n = 0; n < count; ++n) {
    dst4[0] = float(mat[0][0] * src2[0] + mat[3][0]);
    dst4[1] = float(mat[1][1] * src2[1] + mat[3][1]);
    dst4[2] = mat32;
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_sd(const SkScalar mat[][4],
                    const double* SK_RESTRICT src2,
                    int count,
                    double* SK_RESTRICT dst4) {
  for (int n = 0; n < count; ++n) {
    dst4[0] = mat[0][0] * src2[0] + mat[3][0];
    dst4[1] = mat[1][1] * src2[1] + mat[3][1];
    dst4[2] = mat[3][2];
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_af(const SkScalar mat[][4],
                    const float* SK_RESTRICT src2,
                    int count,
                    float* SK_RESTRICT dst4) {
  SkScalar r;
  for (int n = 0; n < count; ++n) {
    SkScalar sx = src2[0];
    SkScalar sy = src2[1];
    r = mat[0][0] * sx + mat[1][0] * sy + mat[3][0];
    dst4[0] = float(r);
    r = mat[0][1] * sx + mat[1][1] * sy + mat[3][1];
    dst4[1] = float(r);
    r = mat[0][2] * sx + mat[1][2] * sy + mat[3][2];
    dst4[2] = float(r);
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_ad(const SkScalar mat[][4],
                    const double* SK_RESTRICT src2,
                    int count,
                    double* SK_RESTRICT dst4) {
  for (int n = 0; n < count; ++n) {
    double sx = src2[0];
    double sy = src2[1];
    dst4[0] = mat[0][0] * sx + mat[1][0] * sy + mat[3][0];
    dst4[1] = mat[0][1] * sx + mat[1][1] * sy + mat[3][1];
    dst4[2] = mat[0][2] * sx + mat[1][2] * sy + mat[3][2];
    dst4[3] = 1;
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_pf(const SkScalar mat[][4],
                    const float* SK_RESTRICT src2,
                    int count,
                    float* SK_RESTRICT dst4) {
  SkScalar r;
  for (int n = 0; n < count; ++n) {
    SkScalar sx = src2[0];
    SkScalar sy = src2[1];
    for (int i = 0; i < 4; i++) {
      r = mat[0][i] * sx + mat[1][i] * sy + mat[3][i];
      dst4[i] = float(r);
    }
    src2 += 2;
    dst4 += 4;
  }
}

static void map2_pd(const SkScalar mat[][4],
                    const double* SK_RESTRICT src2,
                    int count,
                    double* SK_RESTRICT dst4) {
  for (int n = 0; n < count; ++n) {
    double sx = src2[0];
    double sy = src2[1];
    for (int i = 0; i < 4; i++) {
      dst4[i] = mat[0][i] * sx + mat[1][i] * sy + mat[3][i];
    }
    src2 += 2;
    dst4 += 4;
  }
}

void Matrix44::map2(const float src2[], int count, float dst4[]) const {
  static const Map2Procf gProc[] = {map2_if, map2_tf, map2_sf, map2_sf,
                                    map2_af, map2_af, map2_af, map2_af};

  TypeMask mask = this->getType();
  Map2Procf proc = (mask & kPerspective_Mask) ? map2_pf : gProc[mask];
  proc(fMat, src2, count, dst4);
}

void Matrix44::map2(const double src2[], int count, double dst4[]) const {
  static const Map2Procd gProc[] = {map2_id, map2_td, map2_sd, map2_sd,
                                    map2_ad, map2_ad, map2_ad, map2_ad};

  TypeMask mask = this->getType();
  Map2Procd proc = (mask & kPerspective_Mask) ? map2_pd : gProc[mask];
  proc(fMat, src2, count, dst4);
}

bool Matrix44::preserves2dAxisAlignment(SkScalar epsilon) const {
  // Can't check (mask & kPerspective_Mask) because Z isn't relevant here.
  if (0 != perspX() || 0 != perspY())
    return false;

  // A matrix with two non-zeroish values in any of the upper right
  // rows or columns will skew.  If only one value in each row or
  // column is non-zeroish, we get a scale plus perhaps a 90-degree
  // rotation.
  int col0 = 0;
  int col1 = 0;
  int row0 = 0;
  int row1 = 0;

  // Must test against epsilon, not 0, because we can get values
  // around 6e-17 in the matrix that "should" be 0.

  if (SkScalarAbs(fMat[0][0]) > epsilon) {
    col0++;
    row0++;
  }
  if (SkScalarAbs(fMat[0][1]) > epsilon) {
    col1++;
    row0++;
  }
  if (SkScalarAbs(fMat[1][0]) > epsilon) {
    col0++;
    row1++;
  }
  if (SkScalarAbs(fMat[1][1]) > epsilon) {
    col1++;
    row1++;
  }
  if (col0 > 1 || col1 > 1 || row0 > 1 || row1 > 1) {
    return false;
  }

  return true;
}

///////////////////////////////////////////////////////////////////////////////

void Matrix44::dump() const {
  static const char* format =
      "|%g %g %g %g|\n"
      "|%g %g %g %g|\n"
      "|%g %g %g %g|\n"
      "|%g %g %g %g|\n";
  SkDebugf(format, fMat[0][0], fMat[1][0], fMat[2][0], fMat[3][0], fMat[0][1],
           fMat[1][1], fMat[2][1], fMat[3][1], fMat[0][2], fMat[1][2],
           fMat[2][2], fMat[3][2], fMat[0][3], fMat[1][3], fMat[2][3],
           fMat[3][3]);
}

///////////////////////////////////////////////////////////////////////////////

static void initFromMatrix(SkScalar dst[4][4], const SkMatrix& src) {
  dst[0][0] = src[SkMatrix::kMScaleX];
  dst[1][0] = src[SkMatrix::kMSkewX];
  dst[2][0] = 0;
  dst[3][0] = src[SkMatrix::kMTransX];
  dst[0][1] = src[SkMatrix::kMSkewY];
  dst[1][1] = src[SkMatrix::kMScaleY];
  dst[2][1] = 0;
  dst[3][1] = src[SkMatrix::kMTransY];
  dst[0][2] = 0;
  dst[1][2] = 0;
  dst[2][2] = 1;
  dst[3][2] = 0;
  dst[0][3] = src[SkMatrix::kMPersp0];
  dst[1][3] = src[SkMatrix::kMPersp1];
  dst[2][3] = 0;
  dst[3][3] = src[SkMatrix::kMPersp2];
}

Matrix44::Matrix44(const SkMatrix& src) {
  this->operator=(src);
}

Matrix44& Matrix44::operator=(const SkMatrix& src) {
  initFromMatrix(fMat, src);

  if (src.isIdentity()) {
    this->setTypeMask(kIdentity_Mask);
  } else {
    this->recomputeTypeMask();
  }
  return *this;
}

Matrix44::operator SkMatrix() const {
  SkMatrix dst;

  dst[SkMatrix::kMScaleX] = fMat[0][0];
  dst[SkMatrix::kMSkewX] = fMat[1][0];
  dst[SkMatrix::kMTransX] = fMat[3][0];

  dst[SkMatrix::kMSkewY] = fMat[0][1];
  dst[SkMatrix::kMScaleY] = fMat[1][1];
  dst[SkMatrix::kMTransY] = fMat[3][1];

  dst[SkMatrix::kMPersp0] = fMat[0][3];
  dst[SkMatrix::kMPersp1] = fMat[1][3];
  dst[SkMatrix::kMPersp2] = fMat[3][3];

  return dst;
}

}  // namespace skia
